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M. Castagnetti, W. Rigamontiwhereas ureteric stones require fluoroscopic focusing.Number of shock waves should be individualized accordingto patient weight, and stone size and composition.Differences might also be related to the shock waves generator.Paediatric series of SWL report stone-free rates 3 monthsafter treatment between 70 and 100%. High rates havebeen reported even with big stones of 20-30 mm indiameters, staghorn stones, and stones located in thelower-pole. These cases, however, might require multipletreatment sessions.Current data suggest that systematic preoperativeureteric stents insertion is unnecessary.After SWL, complications occur in about 20% of cases.Major complications include haematuria, steinstrasse,ureteric obstruction, and urinary tract infection with orwithout fever. Steinstasse occurs in 6 to 20% of cases.Spontaneous stone clearance is common despite thesmall ureteric diameter. Therefore, expectant managementwith close follow-up is adequate. Alpha-blockers can beadded to enhance stone clearance from the distal ureter.Haematuria and haematoma formation are exceptionalafter SWL and do not require any treatment. Urinary tractinfection may follow stone fragmentation or overlap othercomplications such as steinstasse formation.The procedure does not seem to cause any damage to thesurrounding anatomical structures, such as the ovaries,during treatment of distal ureteric stones in female patients.SWL does not seem to affect long-term renal growth,ispilateral or total glomerular filtration rate, or differentialrenal function, as evaluated by dimercaptosuccinicrenal scans. Consistently, SWL in paediatric patients doesnot seem to be associated with an increased long-termrisk of hypertension, diabetes mellitus, renal failure, orproteinuria. Intuitively, type of SWL generator, shockwave numbers and dosage, on one side, and patient age,on the other, might affect the outcome, but data are stilltoo limited to draw conclusions about these variables.DISCUSSIONThis overview supports the principle that SWL is a viableoption in the treatment of upper urinary tract stones inchildren. SWL has a nearly 100% success rate withstones < 20 mm, not located in the lower pole, and otherthan staghorn. Although SWL has been used also inthese instances, percutaneous nephrolithotomy has beenproposed as an alternative to increase stone-free ratesand reduce complications. This approach appears to beincreasingly reasonable with miniaturization of instrumentsand after the introduction of holmium laser technology.Nevertheless, percutaneous nephrolithotomy isalso a more invasive approach, that does not ensure a100% stone-free rate, can be associated with significantmorbidity (20% haemorrhage), and increases hospitalstay. Similar arguments apply to the use of ureteroscopythat has been recommended by some as an alternative forureteric stones > 10 mm, but may be associated with significantcomplications such as ureteric perforation andstricture.CONCLUSIONSData from current literature warrant an attempt of treatmentof urinary stones by SWL in many cases includingvery young patients, patients with big stones or stones inlower-poles, and patients with staghorn calculi. The procedureseems to be safe.REFERENCES1. Jayanthi VR, Arnold PM, Koff SA: Strategies for managing uppertract calculi in young children. J Urol 1999; 162:1234-72. Raza A, Turna B, Smith G, et al: Pediatric urolithiasis: 15 yearsof local experience with minimally invasive endourological managementof pediatric calculi. J Urol 2005; 174:682-5.3. D'Addessi A, Bongiovanni L, Racioppi M, et al: Is extracorporealshock wave lithotripsy in pediatrics a safe procedure? J Pediatr Surg2008; 43:591-6.CorrespondenceMarco Castagnetti, MDSection of Paediatric Urology, Urology UnitDepatment of Oncological and Surgical SciencesUniversity Hospital of PadovaMonoblocco OspedalieroVia Giustiniani, 2 - 35100 Padua, Italymarcocastagnetti@hotmail.com50Archivio Italiano di Urologia e Andrologia 2010; 82, 1